Tank cleaning device and method



Sept. 4, 1962 M. T. KENNEDY, JR

TANK CLEANING DEVICE AND METHOD Merritt TKenned ,J

'7 Sheets-Sheet l INVENTOR ATTORNEY BY V Filed May 14, 1958 P 4, 1962 M. T. KENNEDY, JR 3,052,574

' TANK CLEANING DEVICE AND METHOD Filed May 14, 1958 7 Sheets-Sheet 2 l NVE NTOR Mel-r1166 fffemzeizy,fn

ATTORNEY Sept. 4, 1962 M. T. KENNEDY, JR

TANK CLEANING DEVICE AND METHOD 7 Sheets-Sheet 3 Filed May 14, 1958 Sept. 4, 1962 M. T.-KENNEDY, JR

TANK CLEANING DEVICE AND METHOD 7 Sheets-Sheet 4 Filed May 14, 1958 INVENTOVR Merrihfifenne Cflw ATTORNEY Sept. 4, 1962 Filed May 14, 1958 TTc- 1B 7 Sheets-Sheet 5 20th. Stripe of lst. Cycle NOZZLE DIRECTION AT 30th. Stripe END of 2nd. Cycle CYCLE 2Ist. Stripe of lst. Cycle lst. Stripe 4 START of lst. Cycle of CYCLE lst. Stripe of 2nd.Cycle 2nd. Stripe of lst. Cycle NOZZLE DIRECTION AT 2nd. Stripe START of 2nd. Cycle CYCLE 3rd. Stripe of let. Cycle 3rd. Stripe of 2nd. Cycle Y 4th. Stripe of lst. Cycle INVENTOR ATTORNEY Sept. 1962 M. T. KENNEDY, JR 3,052,574

TANK CLEANING DEVICE AND METHOD Filed May 14, 1958 7 Sheets-Sheet 6 INVENTOR I ill-217666 Zifwzneci Sept. 4, 1962 M. T. KENNEDY, JR

TANK CLEANING DEVICE AND METHOD Filed May 14, 1958 7 Sheets-Sheet 7 ATTORNEY States The present invention relates to a device and method for cleaning the inside wall surfaces of tanks, vats, drums, containers, etc.

In accordance with certain features of the present invention, the cleaning device comprises one or more reaction nozzles mounted for rotation about an axis and mounted for simultaneous rotation bodily about another axis at right angles to said first mentioned axis. The dual axis rotation of the nozzle or nozzles is entirely automatic. As the liquid used for washing passes through the discharge end of each nozzle, the reaction created turns the nozzle about one of the axes hereinafter referred to as the nozzle axis and a drive connection between the nozzle and the housing or turret carrying the nozzle causes the housing or turret to rotate simultaneously about the other axis, hereinafter referred to as the housing or turret axis. The resulting simultaneous rotations of each nozzle about the two axes at right angles to each other, causes the nozzle to project a high velocity cleaning jet against the inside of the tank walls following a helical jet impingement stripe pattern on said walls around the top, bottom and sides of the tank. The term helical is used herein in a broad sense, since the tank may be of rectangular, cylindrical or other shape.

The liquid employed for washing and for driving the nozzle or nozzles about the two axes must be under sufficient pressure to produce therefrom high velocity jets for effective impactive cleaning and the nozzle or nozzles are therefore driven by the reaction of the liquid at high speed unless controlled. Since the extent of cleaning of a wall surface depends inversely as the rate of sweep of the cleaning jet over the surface, it is seen that the rapid cutting of the jet across the surface to be cleaned is not usually desirable. Moreover, since the spaces between direct jet impingement stripes on the wall surfaces may have to depend on run downs of liquids from these stripes for cleaning, and since the amount of this run down liquid depends on how slowly the cleaning jet traverses the wall surface, it is seen that a fast traverse of the jet across the wall surface causes ineffectual washing of these wall spaces. It is, therefore, advantageous to employ a braking mechanism in connection with the cleaning device to slow down and control the rate of revoltuion of each nozzle about its two axes.

One object of the present invention is to provide a new and improved tank cleaning device of the reaction nozzle type, which is small, light, portable, compact and comparatively inexpensive to manufacture and which is made of a minimum number of parts.

Another object of the invention is to provide in conjunction with a tank cleaning device a new and improved braking device, which reduces the speed of a cleaning device of the general reaction nozzle type described, which does not generate excessive friction heat, which does not wear out, and which occupies a minimum of space.

A further object of the invention is to provide new and improved means whereby the speed of rotation of the nozzles about the two axes at right angles to each other may be easily and quickly adjusted.

Another object of the invention is to provide new and improved adjustable reaction nozzle means for a cleaning device of the general dual axis type described de atent signed to permit adjustment in the nozzle or nozzles to control the speeds thereof, without materially changing the jet impingement stripe pattern generated.

A further object of the invention is to provide a connection with a modification thereof, a new and improved cleaning device of the dual axis type described, which is designed to be connected in series with one or more similar cleaning devices for simultaneous operation, as for example in a deep tank, at different levels.

Another object of the present invention in connection with a modification thereof, is to provide a new and improved cleaning device of the dual axis type described having gear transmission parts housed and protected against contact with the cleaning liquid passing through the device.

A further object of the invention is to provide a new and improved cleaning device and a new and improved cleaning method employing such a device for effectively cleaning long tanks even in the end regions of said tank remote from the device.

In accordance with some features of the present inven tion, the braking device comprises a braking member of irregular contour immersed in a body of viscous liquid sealed in a casing or drum member, one of said members being stationary, while the other member has a drive connection with the nozzle, so that as the nozzle rotates about its axis, the latter member also rotates in relation to the viscous liquid, thereby exerting resistance to the rotation of the nozzle about its axis due to friction or the inertia of the liquid to movement or to both. The reaction nozzle or nozzles are thereby slowed down to the point where effective cleaning of the wall surfaces is assured. The braking member is desirably shaped to impart a shearing action on the viscous braking liquid smoothly with a minimum of stresses and vibrations on the cleaning device.

In accordance with another feature of the present invention, two nozzles are provided on a common axis having inlet legs respectively extending substantially radially in opposite directions from a common inlet chamber or nozzle eye in axial alignment, and discharge legs respec tively reversed 180 so that the axes of said discharge legs extend substantially parallel to the common alignment axis of said inlet legs and the nozzles will be U-shape. The discharge legs of the two nozzles are relatively turned in relation to the alignment axis of the inlet legs to create reaction forces on the nozzles upon the passage of cleaning liquid therethrough tending to rotate both nozzles in the same direction and with equal forces about the axis of rotation of the nozzle. To develop maximum reaction forces on the nozzles tending to rotate them about the axis of rotation of the nozzle, the discharge axes of the discharge legs should extend in a common plane with the alignment axis of the inlet legs at right angles to the nozzle axis and the discharge legs should be turned in opposite directions from the alignment axis of the inlet legs.

As a further feature, the nozzle inlet legs constitute swivel legs by which the axes of the discharge legs may be adjusted about the alignment axis of the inlet legs. This adjustment permits the planes of flow of the liquid through the nozzles to be changed in relation to the plane at right angles to the axis of rotation of the nozzles, and correspondingly reduces the reaction forces on the nozzles, so that those nozzles rotate about their axis at a lower speed, the extent of speed reduction depending on the extent of deviation of said planes of flow from the plane at right angles to the axis of rotation of the nozzles. When the nozzle discharge legs have been turned from the plane at right angles to the axis of rotation of the nozzle, the components of reaction forces around said axis will be zero.

As a further feature, a gear connection is provided between an adjusting member and both nozzle inlet swivel legs to effect simultaneous adjustment of the nozzles in response to the operation of said member, for the purpose and in the manner described.

As another feature ofthe present invention, the flow of cleaning liquid through the cleaning device is along the axis of rotation of the housing or turret, and the cleaning device is constructed to permit a cleaning device which is adapted to be employed singly to be modified slightly in accordance with a modification, to permit a number of such cleaning devices to be interconnected in flow series and operated from the same cleaning liquid coursing through the devices in series. Such cleaning devices with series flow connections are particularly useful in cleaning deep tanks, where a single cleaning device cannot effectively clean all levels of the tank, or may be employed to attain more concentrated cleaning action.

Cleaning devices of the dual axis type described are commonly operated with the axis of the housing or turret extending vertically and the nozzle axis extending horizontally. It has been determined in accordance with the present invention, that a cleaning device so mounted, will in operation generate a helix comprising a series of successive convolutions extending in vertical planes and extending substantially radially at equal angles apart in relation to the housing or turret axis, when viewed in top elevation. The vertical planes of these jet convolutions intersecting the walls of the tank near the region midway between the ends of the tank in the vicinity of the cleaning device will be comparatively close together. The distances between successive impingement stripe sections progressively increase as the ends of the tank are approached, so that in the vicinity of the ends of the tank, the vertical planes of the jet convolutions, intersect the walls of the tank along stripe areas far apart. The impingement of the jets against the tank walls at these remote tank regions are, therefore, along successive stripe areas so far apart, as to preclude the possibility of elfective cleaning of the tank walls between these areas. It has been found in accordance with the present invention, that if the cleaning device has its housing or turret axis extending horizontally and along the length of the tank, the nozzle rotating about its own axis and simultaneously about the housing or turret axis, will generate jet convolutions in substantially radial planes at equal angles apart in relation to the latter axis, when said convolutions are viewed in side elevation along the length of the tank and will be parallel to the longitudinal center line of the tank. These radial jet convolutions planes will intersect the tank waf'l at spaced areas equally spaced along the full length of the tank, so that the distances between jet impingement stripe sections will be the same along the full length of the tank, assuming that the cleaning device is located in the transverse center of the tank, but in any case the spacing between the stripe sections will not vary as they will wtih the cleaning device mounted with the housing axis vertical, thereby assuring effective cleaning of even the remote end. regions of the tank.

Various other objects, features and advantages of the invention are apparent from the. following description and from the accompanying drawings, in which FIG. 1 is a section of a form of cleaning device embodying the present invention, taken approximately along the lines 11 of FIG. 2;

FIG. 2 is a section of the cleaning device taken approximately along the lines 2-2 of FIG. 1;

FIG. 3 is a side elevation of the cleaning device shown partly in section;

FIG. 4 is a detail section of the cleaning device taken on lines 4-4 of FIG. 3;

FIG. 5 is a fragmentary bottom plan view of the cleaning device taken along the lines 5 5' of FIG. 1;

'FIG. 6 is a fragmentary section of another form of cleaning device embodying the present invention;

FIG. 7 is a detail section of the cleaning device taken along the lines 7-7 of FIG. 6;

FIG. 8 is a section of another form of cleaning device embodying the present invention designed to be connected to another cleaning device in series therewith;

FIG. 9 is a detail section showing part of FIG. 8 but showing the cleaning device converted to be used singly;

FIG. 10 is a section of still another form of cleaning device embodying the present invention, and taken on lines 10-10 of FIG. '11;

FIG. 11 is a section of the cleaning device taken on lines 11-11 of FIG. 10;

FIG. 12 is a diagram of the jet impingement stripe pattern generated by the cleaning device of the present invention on the tank wall surfaces to be cleaned;

FIG. 13 is a diagrammatic side view showing the cleaning device of the present invention in a tank to be cleaned, said device being shown oriented with the housing axis of rotation vertical and the nozzle axis of rotation horizontal;

FIG. 14 is a diagrammatic top plan view of the jet convolutions generated by the cleaning device oriented in the manner shown in FIG. 13 in an elongated tank;

FIG. 15 is a diagrammatic side view showing the cleaning device of the present invention in a tank to be cleaned, said device being shown oriented with the housing axis of rotation extending horizontally along the longitudinal direction of an elongated tank; and

FIG. 16 is a vertical section of the tank of FIG. 15 showing in end view elevation the jet convolutions generated by the cleaning device oriented in the elongated tank in the manner shown in FIG. 15.

Referring to the embodiment of the invention shown in FIGS. 15 of the drawings, the cleaning device comprises in general a turret 10 in the form of a housing for a cleaning liquid conduit mounted to rotate about an axis A and carrying a pair of nozzles 11 mounted to rotate with the housing about said axis and mounted tov rotate simultaneously about an axis B at right angles to the axis A. FIG. 13 shows one way in which the cleaning device may be supported or suspended in a tank C and operated to clean the tank. This operation will be described more fully hereinafter.

Referring to the construction of FIGS. 1-5 more in detail, the housing 10 comprises a peripheral wall 12 terminating at one end in a cylindrical hub 13. Secured to the other end of the peripheral housing wall 12 by studs 14 is a cover plate 15 terminating in a cylindrical hub 16 in axial alignment with the hub 13 along the housing axis A. Supported in the housing 10 is a cleaning liquid conduit comprising a liquid distributing chamber 17 in the form of a cylindrical sleeve having a series of elongated openings 18 therein uniformly distributed around its entire circumferential wall to serve as flow passageways and screen openings for the cleaning liquid in its course to the nozzles 11. This sleeve 17 is fixed to permit the housing 10 to rotate thereabout and serves as a bearing for the two hubs 13 and 16 of said housing. For that purpose, the sleeve 17 near one end has a circumferential flange 24 to seat the cover plate 15 and has a cylindrical bearing 21 beyond said flange for the housing hub 16. A bushing 22 of sealing material such as glass impregnated Teflon (tetrafluoroethylene resin) is interposed between the housing cover plate 15 and the sleeve 17 in the region of the housing hub 16 to hermetically seal the housing around said hub and to serve as a bearing.

The other end of the sleeve 17 is externally reduced to define an annular shoulder to receive a washer 23 against which the hub 13 of the housing abuts and the section 24 of the sleeve beyond said washer serves as a bearing for said hub. A bushing 25 of sealing material such as glass impregnated Teflon (tetrafluoroethyL ene resin) is interposed between the housing 16 and the sleeve 17 in the region of the housing hub 13 to hermetically seal the housing around said hub and to serve as a hearing.

The sleeve 17 is closed near one end by an imperforate wall 27 integral with the circumferential wall of the sleeve and of conical shape tapering with concave curvature to a central pointed end to afford streamline flow of the liquid towards the openings 18 of the sleeve as said liquid reaches said wall 27. Locked to the other end of the liquid distributing sleeve 17 is a liquid inlet tube 30. This inlet tube St? has an external thread engaging an internal thread at one end of the sleeve 17 and this sleeve is provided with an internal annular shoulder 31 to seat and thereby limit the inlet tube in its threaded engagement with the sleeve, thereby lock ing the sleeve and the tube together against relative rotation. The outer end of the inlet tube St has a head 32 externally enlarged in diameter to receive an hexagonal mounting nut 33 with an internal threaded bore 34 communicating with the interior of the sleeve 17 through the tube and has an external conical seat 35' engaging a corresponding internal conical seat 36 at one end of the mounting nut to form a slippable connection between said inlet tube and said mounting nut. An O-ring 37 in the mounting nut 33 engaging the head 32 of the inlet tube 30 seals the connection between the inlet tube and the mounting nut.

The mounting nut 33 is adapted to be attached to a hose or pipe connection 38 FIG. 13) leading from a source of liquid supply and serving as a conduit for the liquid and may serve as a means for supporting or suspending the cleaning device in the tank C to be cleaned. The conical seating connection 35 and 36 between the inlet tube 30 and the mounting nut 33 permits the inlet tube 30 and therefore, the liquid distributing sleeve 17 to be rotated in relation to the mounting nut when no liquid is flowing through the cleaning device. This slippable connection between the mounting nut 33 and the inlet tube 30 is advantageous especially during the mounting of the cleaning device to a hose or pipe connection, since it prevents the sleeve 17 from being turned as a handle to lock the mounting nut onto the hose or pipe connection and, therefore, prevents the possibility of the gears to be described, forming part of the drive connection between the nozzles 11 and the housing 10 from being stripped. However, when the liquid supply is turned on, and the cleaning device is in operation, the pressure of the liquid acting on the stationary mounting nut 33 and the inlet tube 30 tending to separate them axially, presses them together at their conical seats '35 and 36 and, therefore, holds the tube and consequently the liquid distributing sleeve 17 connected thereto stationary.

The housing 10 on one side of the liquid distributing sleeve 17 defines a chamber or passageway 40 along the axis B of the nozzles 11 in communication with the interior of said sleeve through the screen openings 18. This housing chamber 4% leads to the nozzles 11 and terminates at one end in a cylindrical bearing 4:. for the hub 42 of a nozzle carrier 43 separated from said hearing by a suitable bearing bushing 44 made, for example, of glass impregnated Teflon or graphite.

The nozzle carrier 43 is in the form of a T-tube having the hub 42 defining the eye of the nozzle and two cross arms 45- extending in radially opposite directions therefrom to receive the nozzles 11 respectively.

The nozzle device comprises two identical U-shaped nozzles 11, each having an inlet leg 46 threaded onto a corresponding cross arm 45 of the nozzle carrier 43 and a discharge leg 47 to which is threaded a nozzle tip 48 having an insert 50 of fluted internal construction to serve as a stream straightener. The two inlet legs 46 of the nozzles 11 extend in radially opposite aligned directions in relation to the nozzle axis B and the two discharge legs 47 of the nozzles extend with their axes substantially parallel to the alignment axis of the inlet legs 46. With the offsetting of the discharge legs 47 from their respective inlet legs 46, the nozzles become reactance nozzles in which the cleaning liquid as it flows therethrough rotates these nozzles about the axis B of the nozzles. The two discharge nozzle legs 47 are turned to exert equal reactance forces on the two nozzles 11 tending to rotate them in the same direction about the axis B. For that purpose, when the nozzles 11 are mounted for maximum reactance, they extend as shown in FIGS. 1-5, with the axes of their discharge legs 47 in the same plane at right angles to the nozzle axis B and with the two discharge legs turned in opposite directions. The two nozzles 11 may be turned from this position of maximum reactance to change the directions of their discharge legs 47 in relation to a plane at right angles to the nozzle axis B, and to thereby reduce the speed of the nozzles about said axis. The adjusting means for this purpose will be described hereinafter.

As the nozzles 11 rotate about their axis B, they drive the housing 10 about its axis A. The drive connection for that purpose comprises a shaft 55 threaded on to the end wall 56 of the nozzle carrier 43 as to be rotated with the nozzles 11 about their axis B and extending along and centered with respect to the nozzle axis B. Secured to this shaft 55 is a worm 57 meshing with a worm wheel 58 threaded onto and thereby aflixed to the liquid distributing sleeve 17. Since the sleeve 17 is fixed against rotation while the liquid is coursing through the cleaning device, the worm wheel 58 will also be fixed and the worm 57 revolving about its axis as a result of the rotation of the nozzles 11 about their axis B will, therefore, travel around the worm wheel 58. Since the housing It carries the worm 57, the movement of the revolving worm about the fixed worm wheel 58 will cause the housing to move with said worm wheel about the sleeve 17 and the axis A of said housing.

As the nozzles 11 make one revolution about the axis B, the worm '57 will make a corresponding revolution and will, therefore, move along the worm wheel 58 the distance equal to one tooth, two teeth, three teeth or four teeth, according to whether the worm is a single thread, double thread, triple thread or a quadruple thread gear. If for example, the worm 57 is a single thread gear, then the worm will travel along the worm wheel 58 a distance equivalent to one tooth of said wheel when said worm rotates one revolution about its axis. Therefore, if the worm wheel 58 has m number of teeth, the worm 57 if provided with a single thread, will make m number of revolutions before returning to its starting point on the worm wheel. Translating this relationship into terms of actual operation, it means that when the housing 10 makes one complete revolution about its axis A, the nozzles 11 will make m number of revolutions about their axis B. Therefore, each nozzle 1?. will generate a number of successive jet impingement stripes on the tank walls corresponding to the number of teeth on the worm wheel 58, starting from one wall section and returning to the same wall section for each turn of the housing 10 about its axis A. Each nozzle 11, therefore, projects a high velocity cleaning jet against the tank walls following a helical impingement stripe pattern through one cleaning cycle around the top, side and bottom tank wall for each turn of the housing 10 about the axis A of said housing. At the end of the first washing cycle corresponding to one turn of the housing 10 about its axis A, the last jet impingment stripe on a wall surface will be in phase with the first stripe on said surface, so that if the washing is continued, at the beginning of the second cycle, the first jet impingement of said second cycle will register and be superimposed on the first jet impingement stripe of the first cycle and all successive jet impingement stripes of the second cycle will register with and be superimposed on the successive impingement stripes respectively of the first cycle. As a result, for successive washing cycles 7 through successive turns of the housing 16 about its axis A, the same stripe areas of the tank walls will receive direct jet impingement, while the intervening areas must depend on run downs of the liquid from the direct jet impingement areas for cleaning, unless the level of the cleaning device is changed.

In accordance with a feature of the present invention, the worm '7 and the worm wheel 5% are designed to produce for successive turns of the housing 10 about the axis A successive washing cycles which are phasically offset, so that the jet impingement stripe pattern generated during each washing cycle is phasically offset from the jet impingement stripe pattern generated during the next preceding washing cycle. This relationship between the jet impingement stripe patterns of successive cycles is attained in accordance with the present invention by employing a multiple thread worm 57 and by employing a worm gear 58 with a number of teeth which when divided by the number of threads in the worm produces a mixed number and not a whole number. This relationship requires m/n to be a mixed number, where m is the number of teeth in the worm gear 58, and n is the number of threads in the worm 57 but more than one. For example, the worm 57 may be a double thread worm, and the worm wheel 58 will have an odd number of teeth, so that the quotient of these numbers will be a mixed number consisting of a whole number and a fraction of one-half. More specifically, in the specific example of the cleaning device illustrated, the worm wheel 58 has 41 teeth and the worm 57 is a double thread gear. FIG. 13 illustrates the jet impingement pattern generated with this specific teeth and thread relationship of the intermeshing gears 57 and 58. In this diagram of FIG. 13, the stripes are shown horizontal only for purposes of illustration but may extend in any direction. Moreover the directions of each nozzle at the beginning and end of the cycles are shown extending vertically but these directions represent the directions of the nozzles about the housing axis A, transverse to the direction of the nozzle about its axis B.

It can be seen from this illustration of FIG. 13 that for the first washing cycle during the first turn of the housing lit about its axis A, each nozzle will make twenty and onehalf (2.0 /2) turns about its axis B and will generate jet impingement stripes on the tank walls starting with the first stripe at one region and returning to the vicinity of said region with the 21st stripe. The twenty-second stripe, however, does not coincide with the first stripe of the first cycle but will cut midway between the first and second stripe, and all succeeding stripes will be similarly phasically offset in relation to the other stripes of the first cycle. At the end of the second washing cycle, the last impingement stripe of said cycle Will be in phase with the first impingement stripe of the first cycle, so that the next impingement stripe at the beginning of the third cycle will coincide with the first impingement stripe of the first cycle and the impingement stripes during this third cycle will register with and be superimposed upon the impingement stripes of the first cycle. Therefore, with the specific worm and worm wheel design described, the jet impingement stripes of each cycle will be phasically offset from the jet impingement stripes of the preceding cycle, and the jet impingement stripe patterns will repeat themselves for every other turn of the housing 1'0 about its axis A. As a result of this jet impingement pattern, the cleaning device may be employed for only one cycle corresponding to one turn of the housing 10 about its axis A, to attain rough coverage of the wall from top to bottom and the cleaning device may be continued for a second cycle during which the wall areas between the previously jet impinged areas are directly impinged by the jets, thereby assuring a more thorough wall coverage during the second cycle. Of course, the cleaning can be continued beyond the second cycle according to the extent of cleaning required.

Since there are two nozzles 11 directing streams in opposite directions, the cycles described are effected in duplicates with simultaneous jet impingements on opposite sides of the tank walls.

The reactance nozzles 11 will be driven at a speed too high to eifect thorough cleaning. To reduce the speed of the nozzles 11, a liquid braking or damping device is employed. This brake device comprises in general a brake member of irregular contour, that is a contour aside rorn cylindrical, conical or that having a circular crosssection throughout its axial length, immersed in a body of damping or braking liquid. A connection from the nozzles 11 causes the body of braking liquid and the brake member to rotate relatively as the nozzles rotate, and the resistance created by this relative rotation slows down the rotation of the nozzles 11 about the axis 13 and thereby also slows down the rotation of the housing 16 about its axis A.

More specifically, the worm 5'7 forms an integral part of a casing or drum 65 of cylindrical shape forming an integral axial continuation of the nozzle shaft so as to rotate therewith. The rear end of the drum is journalled in a bearing 66 forming part of the peripheral wall 12 of the housing 7.9 and separated therefrom by a bushing 67 of suitable bearing and sealing material, such as glass impregnated Teflon.

The rear end of the drum 65 is closed by a cap 68 threaded thereon and provided with holes 74) to receive a turning tool for assembly. The drum 65 sealably encloses a body '71 of viscous liquid such as a viscous liquid grease rotating with the drum as it is driven by the nozzles 11 about the axis B. Immersed in the body 71 of viscous liquid is a brake member 72 presenting a series of braking surfaces extending laterally of its axis of rotation and adapted to shear through the body of viscous liquid in the rum 65. in the specific form shown, the brake memer '72 is in the form of a worm and these braking or shearing surfaces constitute the helical faces of the worm. This worm '72 is held against rotation in relation to the housing 10 and for that purpose has integral or otherwise rigid therewith at one end an axle 73 supported in an end wall 74 of the drum 65 with a snug bearing fit and has at the other end a spindle 75 passing through the cap 68 with a snug fit and threaded into a fastening strap 75 secured at its ends to the peripheral wall 12 of the housing lit? by studs 77. An O-ring 78 between the spindle 75 and the cap 68 prevents leakage along said spin dle and the strap 76 serves not only to lock the brake Worm 72 against rotation relative to the housing 10 but also serves to prevent the cap from accidentally unscrew ing from the drum 65.

The axle 73 and spindle 75 are on a common axis coincident with the axis B of the nozzles 11 and that of the drum 65 and as the drum rotates with the nozzles 11 about the axis B, the viscous brake liquid '71 rotates with the drum about the axis B and around the brake worm 72 held against rotation about the axis B. The friction be tween the brake liquid 71 and the brake worm 72 resulting from this action and the effects of inertia on the brake liquid create resistances which slow down the rotation of the nozzles 11 about the axis B and also thereby the rotation of the housing It) about its axis A.

In order to apply the maximum retarding force on the nozzles 11 and at the same time create by the feed action of the brake Worm 72 pressure on the brake liquid 71 tending to move the drum 65 forward towards the nozzles 11, the threads on the brake worm are of high pitch. The thread on the brake worm 72 is slanted in the right direction to eifect this pressure action, and this action presses the cap 68 against the bearing bushing 67 and thereby assures a sealing fit against the escape of cleaning liquid along said hearing.

A single thread on the brake worm 72 could be pitched to the proper degree to produce the retarding efiect de sired, but a worm having a single thread of high pitch will have too much brake inactive space between succes- 9 sive thread convolutions and this might require a longer brake worm. It is, therefore, desirable to make the brake worm 72 of multiple threads, and in the specific example, a brake worm having four threads is considered suitable. The drawings show a brake worm 72 having a double thread merely to simplify illustration.

The pressure of the cleaning liquid acting mainly against the end wall 56 of the nozzle carrier 43 tends to move the nozzles 11 outwardly along the axis B but this is counteracted by the pressure of the cleaning liquid on the drum 65 acting in the opposite direction. The relative areas exposed to these pressures are about equalized but the pressures created by the action of the brake worm 72 on the braking liquid 71 tends to move the drum 65 in the direction to tighten the sealing effected by the bush ing 67, as already described.

It should be noted that the brake drum 65 is enclosed inside the housing, thereby lending compactness to the cleaning device and is in the path of the cleaning liquid on its way from the chamber 17 to the nozzles 11, thereby utilizing this cleaning liquid to carry away the heat from said drum generated by the braking action and cooling said brake drum.

The damping effect of the brake device is somewhat constant but the operating pressures may vary or the conditions may be such requiring selective controls of the speed of the nozzles 11 about the two axes A and B. For that reason, there is provided means for adjusting the angularity of the nozzles for controlling thereby the reaction effect of the cleaning water thereon. To that end, the inlet leg 46 of each nozzle 11 has integral or otherwise rigid therewith a segmental bevel gear 85 extending only around 90. The nozzle carrier 43 has an axle 86 integral or otherwise rigid therewith projecting axially therefrom and supporting for adjustment thereabout an adjusting bevel gear 87 meshing with the two bevel gears 85 on the two inlet legs 46 of the two nozzles. The bevel gear 87 need not extend the full 360 but is mutilated at the sides to provide two similar opposed gear segments 88, each meshing with a corresponding bevel gear 85 and each extending along an angle only suflicient to mesh with the bevel gear 85 through a 90 turn of the latter bevel gear.

A wing nut 90 threaded on the outer end of the axle 85 locks the gear 87 in adjusted position.

When the two nozzles 11 are turned in the position shown in the drawing, they are subjected to maximum re actions of equal forces from the cleaning liquid passing therethrough. In this position, the two discharge legs 47 of the nozzles 11 are turned in opposite directions with their axes in a plane of maximum reaction at right angles to the axis B of rotation of the nozzles. When it is desired to reduce the speed of the nozzles 11, the wing nut 91) is loosened and one of the nozzles 11 is turned about the axis of its inlet leg 46 to bring its discharge leg 47 forward of the plane of maximum reactance at right angles to the axis B of rotation of the nozzles This turning of the nozzle 11 through a selected angle unscrews said nozzle from the nozzle carrier 43 and turns the adjusting bevel gear 87 meshing with its bevel gear 85, causing the other nozzle 11 to turn through the same angle forwardly of the plane of maximum reactance at right angles to the axis B of rotation of the nozzles. In this manner, the two nozzles 11 are adjusted simultaneously through the same angle by a single adjusting manipulation and the reactances on the two adjusted nozzles are automatically maintained equal. The two nozzles can then be locked in adjusted positions by means of the wing nut 90.

When the two nozzles 11 are turned so that their discharge legs 47 extend forward at right angles to the plane of maximum reactance at right angles to the axis B of rotation of the nozzles after an adjustment of 90, the component of reaction tending to rotate the nozzles about said axis is zero. That is, of course, the limit of adjustment, and since in this position, the two discharge legs 47 are in alignment, adjustments are made short of this limiting position. That is why the active gear angle between the gears and 37 is limited to Any adjustment beyond 90 would cause the nozzles 11 to rotate in the opposite directions from that for which they were designed and would cause thereby parts of the cleaning device to become unscrewed.

For cleaning operations, the cleaning device may be suspended or supported with the housing axis A vertical, as shown in FIG. 13, or maybe suspended or supported with the housing axis A horizontal, as shown in FIG. 15. Where the cleaning device may be suspended or supported with the housing axis A vertical, the center of gravity of the nozzle unit, although displaced from the vertical axis A, will remain substantially in the same horizontal plane as the nozzle unit revolves about said axis. No significant gravity complications, therefore, will ensue when the device is so suspended or supported. However, where the cleaning device is suspended or supported with the housing axis A horizontal, as shown in FIG. 15, the center of gravity of the nozzle unit will travel in a substantially vertical plane about the axis A of the housing, so that significant gravity complications may ensue for heavy cleaning devices, or for devices in which the distances between the axis A and B are large, and these complications may cause the speed of the nozzle unit about the axis A to vary as said unit moves about said axis. To counteract the effect of gravity under these conditions, a counterweight may be applied to the construction of FIGS. l-5. To that end, the peripheral wall 12 of the housing 11 has a pair of radial lugs 92 extending to the bearing section 2.4 of the liquid distributing sleeve 17. A container 93 may be secured to the peripheral wall 12 of the housing 19 by means of tWo studs 94 threaded into said peripheral wall and the lugs 92 respectively and by two of the cover plate studs 14. The container 93 contains weights such as small shots and has a removable cover 95 to permit the amount of said weights to be selectively varied. The container 93 with its weights is on the side of the axis A of the housing substantially diametrically opposite of the nozzle unit to serve as a counterweight to counterbalance the effect of gravity on said nozzle unit as it revolves vertically about said axis.

FIGS. 6 and 7 show a modified form of cleaning device in which the braking or damping member instead of being in the form of a brake worm as in the construction of FIGS. 1-5 is in the form of a solid diametrically elongated member 72a tapering symmetrically towards diametrically opposite ends 99 and bounded by opposite similarly convexly curved surfaces 1%. This brake member 72a may replace the brake worm '72 of FIGS. l-5, the constructions remaining otherwise exactly as shown in FIGS. l-S. However, in FIGS. 6 and 7, a modification is shown in which the nozzle shaft 55a extends beyond the housing 16a to form integral therewith a casing or drum 65a closed by a cap 68a having holes 79a to receive a turning tool for assembly, and is supported by a bearing 1111 in the housing through a bushing 102, made for example, from glass impregnated Teflon. The brake member 72a is enclosed in a body of viscous liquid 71a in the drum 65a and has a spindle 75a passing through the cap 68a with a snug bearing fit and threaded into the end Wall of a cover 1113 enclosing the drum 65a and rigidly secured to the housing, as for example, by studs (not shown). A retaining seal 104 and O-ring prevent leakage of the brake liquid from the drum 65a and holes 106 in the cover 1113 serve to drain any cleaning liquid that may leak into said cover from the chamber around the worm 57a.

The inner surface 197 of the peripheral wall of the 1 1 drum 65a is fluted to assure rotation of the body of brake liquid 7111 with the brake drum 65a.

The pressure of the cleaning liquid acting in directions along the axis B of the nozzles (not shown) similar to the nozzles 11 in the construction of FIGS. l5, has a resultant acting along said axis in a direction to press the nozzles outwardly along said axis, causing an annular shoulder 1% on the drum 65a to press against a shoulder 1139 at the end of the bearing 101 through the bushing 1M. to assure hermetic sealing of the chamber defined by the housing 19a around the nozzle shaft 55a.

In the construction of FIGS. 1-5, the flow of the cleaning liquid is along the axis A of rotation of the housing It in the liquid distributing sleeve 17 and is diverted by the closure wall 27 therein radially outwardly through the openings 18 and towards the nozzles 11. One feature of this location of the liquid distributing sleeve 17 along the axis A of the housing is that by eliminating this closure wall 27 so that the liquid distributing sleeve 17 is open at both ends and by providing means for attaching a second cleaning device to the discharge end of this sleeve, a number of these cleaning devices may be connected together in series to effect quick and/ or more concentrated cleaning action or where the tank is deep, to locate two or more cleaning devices at different levels of the tank to assure effective cleaning of the tanks at all levels. With the cleaning devices constructed as described and coupled together in series, the cleaning liquid coursing through the cleaning devices along the axis A of rotation of their housings does not lose substantial pressure head between the cleaning devices.

FIGS. 8 and 9 show a modified construction for carrying out the objects described. In this modified construction, the liquid distributing sleeve 17b corresponding to the sleeve 17 in the construction of FIGS. 15, is open at its discharge end to provide a liquid distributing sleeve which is clear through from one end of the housing 165 to the other along its axis of rotation A. The discharge end of the sleeve 17!) is internally threaded to receive a coupling collar 110 having a neck 111 externally threaded to permit it to be screwed into said sleeve and having an externally threaded head 11?. defining an axially facing shoulder 113 adapted to engage a spacer 114 between the ends of said sleeve and the housing ltlb on the one side and said shoulder on the other side. The coupling collar 110* is locked to the sleeve 17b so that in operation, said collar remains stationary with said sleeve, and does not bear against the spacer 114 with sufl icient pressure to prevent rotation of the housing 10 about the axis A. In all other respects, the cleaning device of FIG. 8 is the same as that of FIGS. 1-5.

In assembling two or more cleaning devices together in series, the coupling collar 11% of the upper cleaning device is screwed into the mounting nut 33 of the lower cleaning device as shown in FIG. 8. This lower cleaning device would be constructed exactly as shown in FIGS. 1-5 with a liquid distributing sleeve 17 closed at its discharge end by the wall 27 formed integrally therewith or may be as shown in FIG. 8, where a third cleaning device is to be added in series to the other two cleaning devices.

In FIG. 8, the mounting nut 33 of the lower cleaning device is shown screwed directly onto the coupling collar 110 so that the two cleaning devices are close together for concentrated cleaning. However, very often, it is required to have the lower cleaning device at a substantial distance below the upper cleaning device to reach diflerent levels of a deep tank. For that purpose, a long hose or pipe connection, preferably straight, is provided between coupling collar 116 of the upper cleaning device and the mounting nut 33 of the lower cleaning device.

When two cleaning devices are connected in series as described, the nozzles of the two devices are set relatively about the aligned axes A of rotation of their housings 10 and 1%, so that the streams projected from the nozzles of the two cleaning devices do not interfere. For that purpose, they may be set so that the two nozzle units of the two cleaning devices are diametrically opposite the axis A of rotation of the housings. Since the two cleaning devices are operated at independent speeds depending on the pressures of the cleaning liquid in the two cleaning devices and the setting of the angles of the nozzles with respect to the axis B of rotation, this setting of the two cleaning devices may change as cleaning progresses. However, this condition would not adversely affect the cleaning operation, since any stream interferences would be of short duration as long as the speeds of the two cleaning devices are different.

With the cleaning device of FIG. 8, it may be desired sometimes to employ the cleaning device singly instead of as part of a series or it may be desired to employ the cleaning device of FIG. 8 as the bottom device of the series. It is a simple matter for that purpose, to remove the coupling collar and replace it by a plug 116 as shown in FIG. 9, having a sleeve closure wall 271) shaped like the wall 27 in the construction of FIGS. 1-5. The cleaning device so plugged, will operate like the construction of FIGS. 1-5.

In the construction of FIGS. 1-5, the worm and worm wheel drive connection 57, 58 between the nozzle shaft 55 and the housing 1% is exposed to the cleaning liquid as it flows from the liquid distributing sleeve 17 through the holes 18, through the passageway 40 and towards the nozzles 11. If the cleaning liquid is not of the extremely destructive or corrosive type, but is for example, plain water, the exposure of the gear transmission 57 and 58 thereto is not serious. Moreover, the worm 57 and worm wheel 58 may be made of nylon and the other parts of the cleaning device may be made of materials such as aluminum and/ or brass, to withstand the corrosion action of the cleaning liquid. However, in spite of these safeguards, due to the highly corrosive nature of the cleaning liquid which might be used, or because this liquid may contain abrasive materials such as sand, it may be desirable to protect the worm and worm wheel drive connection from the action of the cleaning liquid by protectively housing this connection against contact with the cleaning liquid as said liquid flows through the cleaning device. FIGS. 10 and 11 show a modified construction for that purpose.

In the construction of FIGS. 10 and 11, the housing 100 comprises a base wall and an upstanding wall 121 integral therewith and extending across the housing. Side walls 122 and 123 integral or othewise rigid with the base housing wall 120, serve to form with the upstanding housing wall 121 and with said base wall a chamber comprising two adjoining compartments 124 and 125, the compartment 124 being generally cylindrical to receive concentrical therewith the worm wheel 58c, the other compartment 125 being shaped to receive the worm 57c, each of the two compartments being closed on all sides except for a passageway 126 therebetween where these gears intermesh. A cover 127 is connected to the housing 100, this cover having a base plate 128 seated on the top of the walls 121, 122 and 123 and secured to said walls 122 and 123 by means of studs 129. This bases plate 128 closes entirely the chamber compartment 125 and close entirely the cylindrical chamber compartment 124, except for an opening 130 in said base plate surrounded by a bearing hub extension 131 integral with said base plate and extending into the cylindrical chamber 124 coaxially therewith. This cover 127 is also formed with a chamber 132 above the base plate 128 separated entirely from the two chamber compartments 124 and 125 and serving as a flow passageway for the cleaning liquid from the inlet of the cleaning device to the nozzles 11.

An end section 133 of the housing walls 122 and 123 forms with an end section 134 of the cover 127 a bearing for a nozzle carrier 430 similar to the nozzle carrier 43 in the construction of FIGS. 1-5, this hearing being separated from said carrier by a bushing 44c, as for example of glass impregnated Teflon. A shaft 550 secured to the nozzle carrier 430 for rotation therewith, passes through the housing wall 121 with a snug rotative fit, is supported in a bearing 135 in said wall and is sealed by O-rings 136 in said wall. The shaft 550 extends into the chamber compartment 125 and is dampened in the manner described in connection with the construction of FIGS. 1-5 by a braking mechanism comprising a cylindrical casing or drum 650 in the chamber compartment 125 forming the body of the worm 57c and forming also an integral axial continuation of the nozzle shaft 550, so as to rotate therewith. The rear end of the drum 650 is journalled in a bearing 137 and is closed by a cap 680 threaded therein and provided with holes 700 to receive a turning tool for assembly. The drum 65c sealably encloses a body 710 of viscous liquid in which is immersed the brake worm 720. This brake worm 720 is fixed against rotation with the drum 650 by a spindle 75c which forms an axial core extension of said brake worm, which passes through the cap 68c with a snug rotative fit and which is threaded into a fixed plate 760 rigidly secured to the housing 100 by studs (not shown).

The housing cover 127 has a bearing hub 140, which is coaxial with the cylindrical chamber 124 and with the bearing hub 131 and which embraces a liquid distributing cylindrical sleeve 17c with a bearing fit sealed by an O- ring 141. The sleeve 170 has integral therewith at one end a mounting nut 33c or may be connected to the mounting nut through a bevel seated collar as in the construction of FIGS. l-S, and extends into the chamber 132 defined by the cover 127. A series of elongated openings 180 in the sleeve 17c serve as flow passageways for the cleaning liquid from the sleeve towards the nozzles 110. A closure wall 27c at one end of the sleeve 17c integral therewith and shaped like the closure wall 27 in the construction of FIGS. l5 for streamline deflection of the liquid towards the openings 180 is seated on the base cover plate 127 over the bearing hub 131 thereof and an axle integral extension 143 of the sleeve coaxial with the sleeve 17c passes through the bearing hub 131 with a snug bearing fit sealed by O-rings 144 and extends into the cylindrical chamber compartment 124. The lower end of the axle sleeve extension 143 is supported in a bearing 145 in the lower housing base wall 120. The Worm wheel 580 is threaded onto the axle extension 143 and against a shoulder 146 on said axle extension through a gasket 147, so as to be fixed against rotation relative to the housing a. This worm wheel 580 from the chamber compartment 124 extends through the passageway 126 to mesh with the worm 570 in the chamber compartment 125.

Except as described, the construction of FIGS. 10 and 11 is the same as that of FIGS. 1-5 and operates in a similar way. The nozzles 11 rotate about the axis B as the result of the reaction created by the How of the cleaning liquid through the nozzles. The rotation of the nozzles 11 causes at the same time the rotation of the housing 10c about the fixed liquid distributing sleeve 170 by means of the worm 57c and worm wheel 58c, and thereby about the housing axis A at right angles to the nozzle axis B.

FIG. 13 shows a cleaning device of the present invention supported in the tank Oto clean the walls of the tank. In this arrangement, the cleaning device is illustrated as being specifically of the type shown in FIGS. 15, although the other forms of cleaning devices shown can be similarly supported. In the arrangement shown in FIG. 13, a vertical supply pipe or a hose 38 for the cleaning liquid, such as water, is connected to the mounting nut 33 of the cleaning device, and lowered through a manhole or opening 151 in the tank and the device may be supported at any desired level in the tank by a cable or rope 152. The cleaning device is shown in FIG. 13 supported in the tank with the housing axis A vertical and the nozzle axis B horizontal, and as the water flows through the nozzles 11, they rotate about the axis B by the reaction created and at the same time, the housing 10 carrying the nozzles rotates about the housing axis A causing the nozzles to turn also about the axis A. The specific gearing ratio as described is such, that for every complete revolution of the nozzles 11 about its horizontal axis B, the housing 10 with the nozzles 11 will turn about the vertical axis A a fraction of a revolution corresponding to of 360 or about 17.56. Therefore, for every complete revolution of the housing 10 about the vertical axis A, carrying the nozzle 11 with it, the nozzles make 20 /2 revolutions about its horizontal axis B.

The mounting of the cleaning device in the position shown in FIG. 13 will cause each nozzle to generate a helical stream having convolutions D, which are substantially in vertical planes and which when observed in top plan view, as shown in FIG. 14, will extend substantially radially from a center region spaced equal angular distances apart of 360. In FIG. 14, for the sake of simplicity in illustration, only one-half of each stream convolution is shown and these convolutions are shown to radiate from a single point. Actually, the center from which the stream convolutions radiate moves about a center on the axis A, since the vertical plane of the nozzle is spaced from the vertical axis A of the housing 10. However, the distance between this axis A and the plane of the nozzle is small enough compared with the size of the tank, to permit disregarding this distance for the purpose of illustrating certain principles to be discussed.

For cleaning a tank having a vertical depth or horizontal width, which is greater than its length or which at least is not very much smaller than its length, the mounting of the cleaning device in the manner shown in FIG. 13, is suitable. However, where the tank is comparatively long horizontally in relation to its vertical height or horizontal width, then the cleaning pattern generated by each nozzle shown in FIG. 14 may not be suitable. It will be noted from the jet impingement pattern illustrated in FIG. 14, considering only, for example, a wall section 155 along its length, that the distances between successive jet impingement stripes therealong indicated by the distances a, b, c, d, etc., increase progressively as the stream convolutions D approach the ends of the tank. The distances, therefore between successive j'et impingement stripes near the remote end sections of the tank wall may be too far apart to assure efiective cleaning in these remote sections.

It has been determined in accordance with the present invention, that this drawback in the cleaning of horizontally elongated tanks can be remedied by simply turning the cleaning device so that the axis A of the housing 10 extends horizontally along the longitudinal direction of the tank substantially midway between the sides thereof, but not necessarily midway between the top and bottom thereof. FIG. 15 shows the mounting of the cleaning device, such as that of FIGS. 15 but with its housing axis A extending horizontally along the longitudinal direction of a long tank C. For that purpose, the vertical supply pipe or hose 38 has a 90 elbow 156 to connect into the mounting nut 33 through a horizontal nipple. With the cleaning device mounted as shown in FIG. 15, each nozzle will generate a helical stream having convolutions D, which are approximately in planes extending radially from a center region when observed in end elevation looking horizontally along the longitudinal direction of the tank towards one end thereof, as shown in the jet impingement pattern illustrated in FIG. 16 and spaced equal angular distances apart /r1 360). As in the jet impingement pattern illustrated in FIG. 14, FIG. 16 for the sake of simplicity shows only half of each stream convolution, and the stream convolutions are shown to radiate from a single point, when as a matter of fact, the planes of these convolutions would be tangent to a circle centered about the horizontal axis A of the housing. However, because the diameter of the circle is small compared to the size of the tank C, the planes of the convolutions are assumed to radiate from a single point.

It will be noted from the jet impingement pattern of FIG. 16, considering for example, a peripheral wall section 157 of the tank C, that the distances between successive jet impingement stripes therealong indicated by the distances a, b, c, d etc. are equal and these distances between stripes remain the same for the entire length of the tank C. Therefore, the ends of the tank, even though remote from the center of the tank where the cleaning device is located, will be cleaned effectively.

Also, it should be noted from the jet impingement stripe pattern of FIG. 16, that by placing the cleaning device offset from the center position shown, so that it will be closer to one peripheral wall section of the tank than it will be from the diametrically opposite peripheral wall section of the tank, the distances between the jet impingement stripes at said closer wall section will be closer together than they will be at this diametrically opposite section, thereby effecting more thorough and concentrated cleaning at said closer wall section. This feature of the jet impingement stripe pattern with the axis of the housing A extending along the longitudinal direction of the tank is, therefore, also useful, where certain peripheral wall areas require more thorough cleaning than other peripheral Wall areas. For example, the bottom of the tank where most of the sediment collects may be stubborn in its resistance to cleaning. A cleaning device located so that it is closer to the bottom of the tank than it is to the top of the tank and arranged so that the axis A of the housing is horizontal and extends along the longitudinal direction of the tank will perform the necessary cleaning.

While the invention has been described with particular reference to specific embodiments, it is to be understood that it is not to be limited thereto, but is to be construed broadly and restricted solely by the scope of the appended claims.

What is claimed is:

l. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a turret supporting said conduit, means supporting said turret for rotation about a first axis, a nozzle supported on said turret for rotation with said turret about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet, means for rotating said nozzle about said second axis by the energy of the cleaning liquid passing through the nozzle, means automatically operable as said nozzle rotates about said second axis for simultaneously rotating said turret about said first axis, and liquid braking means for retarding the speeds of rotation of said turret and said nozzle about said axes respectively, comprising a drum member containing a braking liquid aside from the cleaning liquid, a brake member immersed in said braking liquid, and drive means operable by the drive action of the nozzle about said second axis for rotating one of said members relative to the other to cause relative rotary movement of the body of braking liquid in said drum member and the brake member immersed therein, said brake member presenting brake surfaces in the braking liquid offering resistances to the relative rotation of the brake member and the body of braking liquid, said resistance being transmitted through said drive means to said nozzle to retard rotation of said nozzle about said second axis.

2. A device for cleaning the walls of a tank as described 16 in claim 1, wherein said brake member is in the form of a Worm.

3. A device for cleaning the walls of a tank as described in claim 1, wherein said=brake member has a contour diametrically elongated in opposite directions from an axis and tapering towards diametrically opposite ends.

4. A device for cleaning the walls of a tank as described in claim 1, wherein the means for rotating the nozzle about said second axis consists of a discharge leg on the nozzle turned in relation to the rest of the nozzle to receive the reaction of the cleaning liquid as it is discharged from said leg as a high velocity jet.

5. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a housing for said conduit, means supporting said housing for rotation about a first axis, a reaction nozzle supported on said housing for rotation with said housing about said axis and for rotation about a second axis substantially at night angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet while said nozzle is rotated by the reaction of the liquid passing therethrough, a shaft connected to said nozzle along said second axis for rotation with said nozzle about said second axis, and supported on said housing to cause it to revolve with said housing about said first axis, a gear drive between said shaft and said housing rotating said housing about said first axis as said nozzle rotates about said second axis, and a liquid braking means for retarding the speeds of rotations of said housing and said nozzle about said axes respectively and comprising a drum member coaxial with 'said shaft and containing a braking liquid thereinpand a brake member immersed in said braking liquid and coaxial with said shaft, said brake member having a contour resisting relative rotation of the braking liquid and the brake member, one of said members being connected to said shaft for rotation therewith, while the other member is secured to said housing against rotation relative thereto. 6. A device for cleaning the walls of the tank, as described in claim 5, wherein said drum member is cylindrical and is rigidly connected to said shaft and the other member is rigidly connected to said housing.

7. A device for cleaning the walls of a tank as de scribed in claim 5, wherein said gear drive comprises a worm secured to said shaft and coaxial therewith for rctation therewith, a worm wheel coaxial with said first axis and meshing with said worm, and means fixing said worm wheel against rotation about said first axis, whereby as said worm rotates it travels along said worm wheel causing the housing to rotate about said first axis.

8. A device for cleaning the walls of a tank, as described in claim 5, wherein said gear drive includes a gear encircling said drum member coaxial therewith and rigidly connected thereto.

9. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, 21 housing for said conduit, means supporting said housing for rotation about a first axis, a reaction nozzle supported on said housing for rotation with said housing about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being conneced to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet while said nozzle is rotated by the reaction of the liquid passing therethrough, a shaft connected to said nozzle along said second axis for rotation with said nozzle about said second axis and supported on said housing to cause said shaft to revolve with said housing about said first axis, a worm connected to said shaft for rotation therewith, a worm wheel coaxial with said first axis and meshing with said worm, means fixing said worm wheel against rotation about said first axis, whereby as said worm rotates it travels along said worm wheel causing the housing to rotate about said first axis, a drum coaxial with said shaft and connected thereto for rotation therewith about said second axis, said worm encircling said drum and being rigidly connected thereto whereby said drum rotates with said shaft about said second axis, said drum containing a braking liquid, a brake member immersed in the braking liquid in said drum, and means rigidly connecting said brake member to said housing, whereby upon rotation of said shaft, the drum in conjunction With the braking liquid and the brake member rotate relatively, retarding thereby the rotation of said shaft.

10. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a housing for said conduit defining a bearing in communication with part of said conduit and defining an annular axially facing shoulder, means supporting said housing for rotation about a first axis, a reaction nozzle supported on said housing for rotation with said housing about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet, means for rotating said nozzle about said second axis by the energy of the cleaning liquid passing through the cleaning device, means automatically operable as said nozzle rotates about said second axis for simultaneously rotating said housing about said first axis and including a shaft rigid with said nozzle and extending along said second axis, and liquid braking means for retarding the speeds of rotation of said housing and said nozzle about said axes respectively, and comprising a drum connected to said shaft for rotation therewith and supported in said bearing, said drum having a cap at one end with an annular axially facing shoulder confronting the shoulder on said bearing, said drum containing a brake liquid, and a brake member immersed in said braking liquid and connected to said housing against rotation relative to said housing, said brake member having a contour resisting relative rotation of the braking liquid and the brake member, said brake member also having a contour tending to feed the braking liquid towards the other end of the drum and to apply pressure to the wall at the latter end to bring the shoulders in sealing running relationship.

11. A device for cleaning the walls of a tank as described in claim 10, wherein the brake member is in the form of a worm.

12. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a housing for said conduit, means supporting said housing for rotation about a first axis, a reaction nozzle supported on said housing for rotation with said housing about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet while said nozzle is rotated by the reaction of the liquid passing therethrough, means automatically operable as said nozzle rotates about said second axis for simultaneously rotating said housingabout said first axis and including a shaft connected to said nozzle along said second axis for rotation with said nozzle about said second axis and supported on said housing to cause said shaft to revolve with said housing about said first axis, and liquid braking means for retarding the speeds of rotation of said housing and said nozzle about said axes respectively, and comprising a drum connected to said shaft for rotation therewith and containing a braking liquid, and a brake member immersed in said braking liquid and connected to said housing against rotation relative to said housing, said brake member having a contour resisting relative rotation of the braking liquid and the brake member, said drum having an external annular shoulder axially facing the nozzle, said housing having a bearing for said shaft and an annular shoulder facing axially away from said nozzle, the shoulder on said drum abutting the shoulder on said housing, said conduit along said shaft presenting axially facing surfaces acted upon by the pressure of the cleaning liquid as said cleaning liquid passes through said conduit towards said nozzle, said surfaces being relatively proportioned in areas to produce a resultant from the pressure of the cleaning liquid acting along said second axis in a direction to press the shoulder on said drum towards the nozzle and against the shoulder on the housing to effect a sealing running fit between said shoulders.

13. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a housing for said conduit, means supporting said housing for rotation about a first axis, -a reaction nozzle supported on said housing for rotation with said housing about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side 'of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet while said nozzle is rotated by the reaction of the liquid passing therethrough, a shaft connected to said nozzle along said second axis for rotation with said nozzle about said second axis and supported on said housing to cause said shaft to revolve with said housing about said first axis, a worm connected to said shaft for rotation therewith, a worm wheel coaxial with said first axis and meshing with said worm, means fixing said worm wheel against rotation about said first axis, whereby as said worm rotates it travels along said worm wheel causing the house to rotate about said first axis, a drum connected to said shaft beyond said worm on the side of said worm opposite said nozzle and containing a braking liquid, a brake member immersed in the brake liquid in said drum, and means rigidly connecting said brake member to said housing, whereby upon rotation of said shaft, the drum in conjunction with the braking liquid and the brake member rotate relatively retarding thereby the rotation of said shaft.

14. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit including a liquid distributing sleeve perforated to permit the liquid to flow out therefrom and having an inlet, a tube secured to the inlet end of said sleeve against rotation relative thereto, and having a head with an annular bevelled seat, a hollow mounting nut embracing the head of said tube and having a bevelled seat engaging the seat on said tube, said seats permitting the tube and sleeve on the one hand and the nut on the other to rotate relatively in the absence of any flow of cleaning liquid through said not and said tube towards the inlet of said sleeve, but frictionally locking said nut and said tube and in turn said sleeve against rotation by the action of the pressure of the cleaning liquid on said tube and said nut when passing said tube and said sleeve, a turret supported on said sleeve for rotation thereabout about a first axis along said sleeve, a nozzle on the outside of the sleeve adapted to receive cleaning liquid discharged from said sleeve and adapted to be rotated by the energy of said cleaning liquid about a second axis substantially at right angles to said first axis, and a drive connection between said turret and said nozzle causing said turret to rotate about said first axis as said nozzle rotates about said second axis.

15. A cleaning device as described in claim 14, wherein said drive connection comprises a Worm wheel embracing said sleeve and rigidly connected thereto, a shaft connected to said nozzle and extending along said second axis, and a worm rigidly connected to said shaft for rotation therewith about said second axis and meshing with said worm wheel.

16. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a turret supporting said conduit, means supporting said turret for rotation about a first axis, a nozzle supported on said turret for rotation with said turret about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet, means for rotating said nozzle about said second axis by the energy of the cleaning liquid passing through the nozzle, and drive means for rotating said housing about said first axis as said nozzle rotates about said second axis and comprising a worm wheel and a worm meshing therewith, said worm having n number of threads, where n is more than one, and

is equal to a mixed number, 'where m is the number of teeth in the worm wheel, whereby the jet impingement stripes generated by the jet projected by the nozzle against the walls of the tank during one turn of the turret about said first axis, is phasically offset from the jet impingement stripes generated by the jet projected by the nozzle against the walls of the tank during the next previous turn of the turret about said first axis.

17. A device for cleaning the walls of a tank comprising a pair of nozzles, means for conducting cleaning liquid to said nozzles, means mounting said nozzles for rotation in unison about an axis, said nozzles having respective inlet legs substantially radially aligned in opposite directions in a plane substantially at right angles to said axis, and having respective discharge legs turned substantially 180 in relation to the corresponding inlet legs to receive reactions from the cleaning liquid passing through the nozzles by which said nozzles are rotated in unison about said axis, means mounting said nozzles for adjustment about the axis of radial alignment of the inlet legs of the nozzles in said plane, and means automatically operable as said nozzles rotate about said axis for simultaneously rotating said nozzles bodily about another axis substan tially at right angles to said first mentioned axis.

18. A device for cleaning the Walls of a tank comprising a pair of similar reaction nozzles having respective inlet legs extending along respective leg axes in different directions laterally from a first axis of rotation, and having respective discharge leg-s similarly turned in relation to the respective inlet legs in directions to receive substantially equal reactive forces from the cleaning liquid as it is, discharged from said nozzles tending to rotate said nozzles in the same direction about said first axis of rotation, means for conducting cleaning liquid to said nozzles, means mounting said nozzles for rotation in unison about said first axis, a single manual adjusting member, means responsive to the manual adjusting movement of said adjusting member for adjusting said nozzles rotatively and simultaneously about respective leg axes to the same extent and in directions to vary the reactive forces received from the cleaning liquid substantially to the same extent as said liquid is discharged from said nozzles, and means automatically operable as said nozzles rotate about said first axis for simultaneously rotating said nozzles bodily about another axis substantially at right angles to said first axis.

19. A device for cleaning the walls of a tank as described in claim 18, wherein said adjusting member comprises an adjusting bevel gear on the face of said nozzles having its axis of rotation substantially coextensive with said first axis, and wherein the means for adjusting said nozzles simultaneously comprises bevel gears secured to said inlet legs respectively for rotation therewith respectively about their leg axes and meshing with said adjusting bevel gear.

20. A device for cleaning the walls of a tank comprising a pair of similar reactive nozzles, means for conducting cleaning liquid to said nozzles, means mounting said nozzles for rotation in unison about a first axis and including a nozzle carrier in the form of a T-tube having radially opposed cross arms, said nozzles having respective inlet legs supported on said cross arms respectively for adjusting action about the radial axes respectively of said cross arms, said nozzles having respective discharge legs similarly turned in relation to the respective inlet legs to impart substantially equal reactions to said nozzles for rotation in the same directions about said first axis, an adjusting bevel gear mounted on said carrier for rotation about said first axis relative to said nozzle carrier, bevel gears connected to said inlet legs respectively for rotation therewith about said radial axes respectively, releasable means for locking said adjusting bevel gear in adjusted rotative position, and means automatically operable as said nozzles rotate about said first axis for simultaneously rotating said nozzles bodily about an axis substantially at right angles to said first axis.

21. A device for cleaning the walls of a tank, comprising a cleaning liquid distributing sleeve having a peripheral wall with one or more discharge openings therearound and open at opposite ends to define an inlet and an outlet at said ends respectively, the open outlet end of the sleeve being adapted to have attached thereto a second cleaning device in series with the first cleaning device, a housing around said sleeve having two hubs for said sleeve ends respectively and defining a passageway for the cleaning liquid discharged from said sleeve through said opening or openings, means for mounting the inlet end of said sleeve for connection to a cleaning liquid supply with said sleeve fixed against rotation, while said housing is rotatable about said sleeve about a first axis, a reaction nozzle supported on said housing for rotation therewith about said first axis and supported for rotation about a second axis substantially at right angles to said first axis as the cleaning liquid passes through said nozzle, said nozzle communicating with said passageway, means for simultaneously rotating the nozzle with the housing bodily about said first axis, and a rotary liquid braking means containing a constant amount of braking liquid aside from the cleaning liquid and supported on said housing outside of said sleeve for retarding the speeds of rotation of said housing and said nozzle about said axes respectively.

22. A device for cleaning the Walls of a tank, as described in claim 21, comprising a removable plug, said sleeve having means near its outlet end for removably receiving said plug to close said sleeve outlet to permit the cleaning device to be employed singly.

23. A device for cleaning the walls of a tank, comprising a housing defining two chambers sealably isolated from each other, one of said chambers having an inlet and an outlet, means mounting said housing for rotation about a first axis, a reaction nozzle on the outlet of said one chamber supported on said housing for rotation with said housing about said first axis and for rotation about a second axis substantially at right angles to said first axis, a shaft secured to said nozzle and extending along said second axis for rotation with said nozzle about said second axis and extending into said one chamber and through a separating wall between chambers with a sealing fit into the other chamber, a liquid braking means in said other chamber including a rotatable member secured to said shaft for rotation therewith in contact with braking liquid for retarding the rotation of said nozzle about said second axis, and a gear train in said other chamber having one of its gears secured to said shaft for rotating said housing about said first axis as said nozzles rotate about said second axis.

24. A device for cleaning the walls of a tank, comprising a housing including a bottom wall, peripheral walls, a transverse wall between said peripheral walls and a separate cover having a cover plate sealed on said walls, said Walls and said cover defining two chambers sealed from each other and separated by said cover plate, one of said chambers having an inlet and an outlet, a peripherally perforated liquid distributing sleeve extending through said inlet into said sleeve, means supporting said housing for rotation about said sleeve along a first axis, a reaction nozzle on the outlet of said one chamber supported on said housing for rotation with said housing about said first axis and for rotation about a second axis substantially at right angles to said first axis, a shaft secured to said nozzle for rotation with said nozzle about said second axis and extending into said one chamber through said transverse wall with a sealing fit and into the other chamber, said sleeve having rigid therewith an axle extending along said first axis through said cover plate and into said other chamber, a worm secured to said shaft in said other chamber, a worm wheel meshing with said worm and secured to said axle in said other chamber, whereby as said shaft rotates about said second axis, the worm moving around the fixed worm wheel moves the housing about said first axis, and liquid braking means for the nozzle enclosed in said other chamber comprising a member secured to said shaft in said other chamber for rotation therewith and a braking fluid in contact with said member.

25. A device for cleaning the Walls of a tank comprising a turret, means supporting said turret for movement about a first axis, said cleaning device being adapted to be supported with said first axis horizontal or vertical, a conduit supported on said turret and having an inlet and an outlet for the cleaning liquid, a nozzle unit supported on said turret at the outlet of said conduit for movement with said housing about said first axis and adapted to be rotated by the energy of the cleaning liquid passing through said nozzle unit about a second axis substantially at right angles to said first axis and spaced therefrom, the center of gravity of said nozzle unit being substantially on said second axis, whereby when said device is supported with said first axis horizontal, said center of gravity moves substantially in a vertical plane about said first axis, drive means for moving said nozzle unit about said first axis With said turret automatically as said nozzle unit rotates about said second axis, means for supporting a counterweight on said turret at a region on the side of said first axis substantially diametrically opposite said center of gravity to counterbalance said nozzle unit as it moves about said first axis when said device is supported with said first axis extending horizontally, and a counterweight removably supported by said counterweight supporting means, whereby said counterweight may be absent when said device is operated with said first axis vertical.

26. .A device for cleaning the Walls of a tank elongated in a horizontal direction and having a length substantially greater than its transverse dimensions, comprising a turret, means supporting said turret for movement about a first horizontal axis extending along the length of said tank, a conduit supported on said turret and having an inlet and an outlet for the cleaning liquid, a nozzle supported on said turret at the outlet of said conduit for movement with said turret about said horizontal axis, means for rotating said nozzle about a second axis substantially at right angles to said first axis by the energy of the cleaning liquid passing through said device, and a drive connection between said nozzle and said turret causing said turret and said nozzle to rotate about said first axis and said second axis respectively at predetermined relative speeds.

27. A method of cleaning walls of a tank elongated in a horizontal direction and having a length substantially greater than its transverse dimensions, which comprises supporting a nozzle in the tank, projecting liquid from said nozzle as a high velocity jet so that the jet impinges on the walls of the tank, causing said nozzle to rotate about a first axis as the jet is discharged therefrom, and simultaneously causing said nozzle to move bodily about a horizontal axis substantially at right angles to said first 22 axis and extending along the length of said tank while maintaining the relative rates of movements of the nozzle about said axes substantially constant to cause said nozzle to generate a helical jet with successive convolutions extending in angularly displaced radial planes when the tank is observed in end elevation.

28. In combination, a pair of tank cleaning devices, each comprising a straight sleeve and a housing supported on said sleeve for rotation about said sleeve and about a first axis along said sleeve, the sleeve of one of said devices having an inlet and an outlet at opposite ends, the sleeve of the other device having an inlet at one end and being closed at the other end, a reaction nozzle on each housing supported thereon for rotation therewith about said first axis and for rotation about a second axis substantially at right angles to said first axis, each of said housings defining a passageway extending from the corresponding sleeve to said nozzle and communicating with the interior of said sleeve, whereby cleaning liquid can flow through each of said devices from the inlet of its sleeve through its passageway and through its nozzle to project a high velocity cleaning jet from the nozzle, means for rotating said housing about said first axis simultaneously and automatically as said nozzle rotates about said second axis, a connection between the outlet of the sleeve of said one device and the inlet of the sleeve of said other device, whereby the cleaning liquid passes through said devices connected in series, and a rotary liquid braking means in each housing containing a constant amount of braking liquid aside from the cleaning liquid and located in said housing outside of and on one side of the corresponding sleeve for retarding the speeds of rotation of said housing and the corresponding nozzle about the axes respectively of said housing and the corresponding nozzle.

29. The combination as described in claim 28, wherein said connection is straight and the sleeves of the two devices and said connection are joined in series in axial alignment along said first axis.

30. The combination as described in claim 29, wherein the two devices extend with said one device directly above the other, with their sleeves and said connection extending substantially vertical, and said connection being substantially long to permit the two devices to operate simultaneously at difierent remote levels in a tank being cleaned.

31. A device for cleaning the walls of a tank as described in claim 1, wherein said brake surfaces extend laterally of the axis of said brake member about which said brake member and said body of braking liquid are relatively rotatable.

32. A device for cleaning the walls of a tank, comprising a cleaning liquid conduit having an inlet and an outlet, a turret supporting said conduit, means supporting said turret for rotation about a first axis, a nozzle supported on said turret for rotation with said turret about said axis and for rotation about a second axis substantially at right angles to said first axis, said nozzle being connected to the outlet side of said conduit to receive the cleaning liquid therefrom and to project the cleaning liquid from said nozzle as a high velocity jet, said nozzle having a discharge leg turned in relation to the rest of the nozzle to receive the reaction of the cleaning liquid as it is discharged from said leg as a high velocity jet, a liquid braking means applying constant braking force for retarding the speeds of rotation of said turret and said nozzle about said axes respectively, and means mounting said discharge leg for adjustment in relation to said second axis to adjust the speed of rotation of said nozzle about said second axis.

33. A device for cleaning the walls of a tank as described in claim 1, wherein said drum member is located in said conduit to be cooled by the cleaning liquid in its passage through said conduit.

References Cited in the file of this patent UNITED STATES PATENTS Thompson Sept. 20, 1927 Clinton Oct. 29, 1929 Thompson May 19, 1931 Butterworth May 26, 1931 Paris Nov. 10, 1931 Butterworth Sept. 13, 1932 24 Bell Feb. 11, 1936 Butterworth June 30, 1936 Veneziano Dec. 1, 1953 Griffith Jan. 17, 1956 Terry Sept. 10, 19 57 FOREIGN PATENTS France Dec. 16, 1919 

27. A METHOD OF CLEANING WALLS OF A TANK ELONGATED IN A HORIZONTAL DIRECTION AND HAVING A LENGTH SUBSTANTIALLY GREATER THAN ITS TRANSVERSE DIMENSIONS, WHICH COMPRISES SUPPORTING A NOZZLE IN THE TANK, PROJECTING LIQUID FROM SAID NOZZLE AS A HIGH VOLOCITY JET SO THAT THE JET IMPRINGES ON THE WALLS OF THE TANK, CAUSING SAID NOZZLE TO ROTATE ABOUT A FIRST AXIS AS THE JET IS DISCHARGED THEREFROM, AND SIMULTANEOUSLY CAUSING SAID NOZZLE TO MOVE BODILY ABOUT A HORIZONTAL AXIS SUBSTANTIALLY AT RIGHT ANGLES TO SAID FIRST AXIS AND EXTENDING ALONG THE LENGTH OF SAID TANK WHILE MAINTAINING THE RELATIVE RATES OF MOVEMENTS OF THE NOZZLE ABOUT SAID AXES SUBSTANTIALLY CONSTANT TO CAUSE SAID NOZZLE TO GENERATE A HELICAL JET WITH SUCCESSIVE CONVOLUTIONS EXTENDING IN ANGULARLY DISPLACED RADIAL PLANES WHEN THE TANK IS OBSERVED IN END ELEVATION. 